Physics - Geometrical Optics Question with Solution | TestHub

The ray parallel to one mirror meets the other at $60^{\circ }$ incidence; the $30^{\circ }$ wedge reduces the incidence angle by $30^{\circ }$ at each reflection: $60^{\circ },30^{\circ },0^{\circ }$, where it strikes normally and retraces its path - (C) correct.

Counting reflections on the way in (3) and back out (2) gives five in all - (A) correct; since the ray retraces, the net deviation is $180^{\circ }$, so (B) and (D) are wrong.